Mesoporous composite of molecular sieves for hydrocracking of heavy crude oils and residues

ABSTRACT

A hydrocracking catalyst having a support of a composite of mesoporous materials, molecular sieves and alumina, is used in the last bed of a multi-bed system for treating heavy crude oils and residues and is designed to increase the production of intermediate distillates having boiling points in a temperature range of 204° C. to 538° C., decrease the production of the heavy fraction (&gt;538° C.), and increase the production of gasoline fraction (&lt;204° C.). The feedstock to be processed in the last bed contains low amounts of metals and is lighter than the feedstock that is fed to the first catalytic bed.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit and priority to Mexican applicationNo. MX/a/2012/012877 with a filing date of Nov. 6, 2012, the disclosureof which is incorporated herein by reference in its entirely.

FIELD OF THE INVENTION

The present invention relates to catalysts for hydrotreating heavy crudeoils and residues. More particularly, the invention relates to acomposite catalyst support comprising composites of mesoporousmaterials, alumina and molecular sieves containing metals of groups VIBand VIII of the periodic table for use in the hydrocracking of heavycrude oils and residue and has particular application in the last bed ofa multi-bed catalyst system for treating heavy crude oils and residues.

BACKGROUND OF THE INVENTION

Hydrotreating of heavy crude oils and residues is difficult due to thepresence of refractory compounds of high molecular weight. Hydrotreatingof heavy crude oils and residues depends on factors such as the catalystused, the type of feed to be treated and the design of the reactors. Inthe hydrotreating process, the catalysts are designed to removeheteroatoms such as sulfur, nitrogen, and metals. The removed sulfur andnitrogen leave the system as gaseous products while metals are depositedirreversibly on the catalyst causing its permanent deactivation.

The design of catalysts for all reactions involved in heavy crude oilhydrotreating is a challenge because the large and complex moleculesthat contain the heteroatoms present diffusion problems in the pores ofthe catalyst and inhibit the adsorption of other reagents in its activesites. The task becomes even more problematic due to the presence ofasphaltenes that cause the formation of coke deposits and deactivate thecatalyst faster.

In general, the literature suggests the use of CoMo and NiMo catalystssupported on alumina.

The properties of the catalysts used depend on the type of feed to beprocessed. Operating conditions for heavy crudes are more severe than inthe case of middle distillates where operating conditions are frommoderate to low. Therefore, the catalysts chemical and physicalproperties, such as pore diameter, surface area, pore volumedistribution, and surface acidity among others, must be different.

Currently, some hydrotreating processes in fixed bed reactors are usingcombinations of different catalysts and metal guard materials. Theseprocesses can contain several reactors including a guard bed reactor.Each reactor contains catalysts for different purposes. For example, inthe literature it is claimed the use of a combination of more than tencatalysts. Some porous solids such as activated bauxite and alumina havebeen used as metal guards. Metals and clays present in the feed, cause ahigher pressure drop during operation. This problem can be overcome byusing a guard bed reactor.

There are patent documents which claim the use of Mo with Ni and/or Co.While others include the use of compounds of groups IA, IIA, VA, VIIA,IIB, IVB, VB, and VIIB using different types of oxides such as alumina,zeolites, silica, silica-alumina, titania, and/or combinations of them.Some of these patent documents are described below.

U.S. Pat. No. 6,399,530 discloses an amorphous silica/alumina with largesurface area, and pore volume, and adequate silica content, to ensurethe desired acidic function for chemical reactions. Silica/alumina isused as support in the preparation of the hydrocracking catalysts havinghigh activity and selectivity towards middle distillates. The catalystalso contains metallic components and a modified ultrastable Y zeolite.

Likewise, U.S. Pat. No. 5,620,590 discloses a catalyst consisting of acombination of hydrogenating metals (Co—Mo, Ni—Mo, Ni—W, and Ni—W—Co),and alpha alumina with ultrastable Y zeolite with crystal size betweenof 0.1-0.5 micron, cell unit of 24.2-24.4 angstroms. The feeds used inthe cracking process having an API gravity in the range of 22 to 31.9°.

U.S. Pat. No. 4,988,659 discloses the preparation of a catalyst composedof co-gels of silica/alumina with high surface area, which contributesto increase both, the activity and the octane number in gasoline. Italso increases the production of light cycle oil, decreases theproduction of heavy cycle oil, and increases the quality of both. Theco-gels can be combined with other components such as zeolites, sievessuch as beta, SAPO's, ALPO's, etc. clays, modified clays, inorganicoxides, metals, coal, and organic substances, etc.

U.S. Pat. No. 4,894,142 discloses a catalyst which consists of a mixtureof i) a hydrogenation metal of groups VI and VIII of the periodic table(Mo, W, Ni, Co), ii) a matrix of a refractory inorganic oxide compositesilica-alumina (45-90%) and alumina (5-45%), iii) crystallinesilicoaluminate (zeolite HY, 2-20%) with unit cell in the range 24.2 to24.4 angstrom. The catalyst is highly selective to the conversion ofheavy hydrocarbons to middle distillates in a temperature range of149-371° C. The feeds used can be diesel, vacuum gas oils,demetallizated products, atmospheric residue, de-asphalted vacuumresidue, and bituminous oils. Preferably gas oil mixtures containing 50%volume of their components with boiling point above 371° C. These feedscontain nitrogen compounds usually present as organonitrogen compoundsin amounts of 1 wppm to 1.0 wt %. They, also contain enough sulfurcompounds to present sulfur contents greater than 0.15 wt %. Thecatalysts of this invention are characterized by having low acidity,measured by temperature programmed desorption of ammonia (NH₃-TPD),which in this case was 1.50.

On the other hand, U.S. Pat. No. 4,818,739 discloses the use ofhydrocracking catalysts for feeds with a boiling point between 198.7 to347.7° C. The catalysts are comprised of at least one non-zeoliticmolecular sieve (NZ-MS) for the hydrocracking process based onsilicoaluminophosphates like SAPO, ELAPSO, MeAPO, FeAPO, TiAPO, FCAPO,and ELAPO. At least one zeolitic aluminosilicate, which may consist of aY zeolite, ultrastable Y zeolite, X zeolite, beta zeolite, KZ-20zeolite, faujasite, LZ-210, LZ-10, ZSM, and a mixture of them containing(0.1 to 20 wt %) rare earths of the groups IIA, IIIA, IIIB, and VIIB ormixtures of them. Besides, at least a matrix of a refractory inorganicoxide, which may be clays, silicas, aluminas, silica-alumina,silica-zirconia, silica-magnesia, alumina-boria, alumina-titania, and amixture of them. Also, a hydrogenating component added by impregnation,which can be cobalt, nickel, and/or molybdenum. The products of thisprocess are characterized for having a high ratio ofiso-paraffins/n-paraffins

U.S. Pat. No. 4,689,137 discloses a catalyst composed of a crystallinealuminosilicate (Y zeolite), with silica/alumina ratio above 6.2, incombination with a refractory porous inorganic oxide. The Y Zeolitecontains rare earths and noble metals (Group VIII), which areincorporated using the ion exchange method. The combination of zeoliteand refractory oxide contains from 4.5 to 6.9 wt % of water, which isnecessary thus the catalyst exhibits a high activity in thehydrocracking reactions. The Y zeolite used as part of the catalyst wasprepared by ammonium exchange with a solution of ammoniumfluorosilicate.

U.S. Pat. No. 4,604,187 discloses a catalyst containing a Y zeolite. TheY zeolite was prepared by exchanging a sodium zeolite with cations ofone or more rare earth elements, followed by calcination, ammoniaexchange and ion exchange of cations of noble metals of Group VIII. Theresulting zeolite is not only highly active to promote catalytichydrocracking reactions but also after the reaction it can beregenerated by coke combustion.

U.S. Pat. No. 4,422,959 relates to the preparation of a catalyticcomposite comprising a silica-alumina support with silica content of 20to 80 wt %. In combination with nickel and vanadium compounds of aconcentration in the range of 0.1-10 wt %. The feed used arehydrocarbons or mixtures of hydrocarbons that are in a range of boilingtemperatures of 200-650° C. It can also be used hydrocarbons from tarsands.

U.S. Pat. No. 4,419,271 relates to a hydrocracking process with acatalyst. The hydrocracking catalyst improves the activity, selectivityand stability producing middle distillates from heavy gas oils. Thecatalyst comprises hydrogenation compounds such as metals of groups VIIImainly cobalt or nickel in combination with Group VI metals such asmolybdenum or tungsten sulfides on a refractory oxide support such asalumina, magnesia, silica-alumina, and zeolite-type crystallinealuminosilicate with high cracking activity such as Y zeolite or rareearths-exchanged Y zeolite. They also have excellent activity forhydrodenitrogenation and hydrodesulfurization.

U.S. Pat. No. 4,111,846 discloses the preparation of inorganichydrosols, particularly titania-alumina-silica hydrosols that serve asbinders for catalytic compositions. The composition of the catalysts forthe conversion of hydrocarbons finally comprises inorganic materialssuch as clays, and crystalline aluminosilicates known as zeolites,aggregates of discrete particles in the range from 20 microns to 6 mm insize. These catalysts may have a porous structure that allows thereactant molecules to enter into the catalyst particles. At the sametime the catalyst particles have the physical strength and densitycharacteristics that allow its use in commercial processes.

U.S. Pat. No. 3,304,254 discloses the improvement of a hydrotreatingcatalyst, characterized by a physical mixture of (1) a crystallinealuminosilicate with low sodium content (<4%), and (2) a hydrogenationcomponent which comprises, in greater proportion, a porous support(crystalline aluminosilicate), and in lower proportion a componentexhibiting hydrogenation activity such as elements of groups VI and VIIIof the periodic table, especially Co (1-8 wt %) and MoO₃ (3-20 wt %).The high molecular weight hydrocarbons or a hydrocarbon mixture, forexample, a petroleum fraction is subjected to cracking in the presenceof hydrogen and catalyst. This process is carried out at temperatures inthe range 427-593° C. This process has the disadvantage of producinglarge amounts of dry gas and an excess of butane.

U.S. Pat. No. 3,459,680 relates to a process to convert organiccompounds in the presence of acidic catalytic sites. Such conversionprocesses include hydrocracking, alkylation, isomerization,polymerization, etc. This process relates to an improved composite,which comprises a crystalline aluminosilicate with an ordered structurewith three-dimensional network characterized because the pores have auniform diameter in the range of 4 to 15 angstroms. The remainingcomposite is comprised of a crystalline aluminosilicate, but it may benon-porous or catalytically inert. The rest of the remaining compositealso contains a porous material. The composite is prepared by mechanicalmixing. These catalysts have attrition resistance, activity,selectivity, and stability for steam deactivation.

U.S. Pat. No. 3,969,222 relates to a hydrotreating process(hydroprocessing) of hydrocarbons or mixtures of them, using a catalyticcomposite of a porous material, a component of palladium or platinum, acomponent of iridium and a component of germanium. The compositecomprises a crystalline aluminosilicate. This process also is directedto the hydrogenation of aromatic rings, ring opening of cyclichydrocarbons, desulfurization, denitrogenation, hydrogenation, etc. Thisprocess consists of two stages; the catalyst is for the second stagewhere the feed used already passed through the first stage.

SUMMARY OF THE INVENTION

The present invention involves the discovery and production of ahydrocracking catalyst having a composite support comprising mesoporousmaterial.

According to a preferred embodiment of the present invention, thecomposite catalyst support comprises mesoporous silica, SBA-15.

According to another embodiment of the invention, the composite catalystsupport of the present invention comprises alumina/molecularsieve/SBA-15, preferably boehmite/zeolite/SBA-15.

According to a further embodiment of the invention, the compositesupport of the present invention is formulated with metals of Groups VIBand VIII of the periodic table to form a catalyst useful forhydrocracking of heavy crude oils and residues.

According to still another embodiment of the present invention, thecomposite support of the present invention is formulated with metals ofGroups VIB and VIII of the periodic table to form a catalyst used forhydrocracking of heavy crude oils and residues, particularly in the lastbed of a multi-bed catalyst system.

With this invention it is possible to obtain a catalyst for use mainlyin the last bed of a multi-bed system in one or more fixed bed reactorsin a process for hydrotreating of heavy crude oils and residues.

The present catalyst composite support is particularly useful in thethird bed of a fixed bed reactor in a process for hydrotreating heavycrude oils and residues, especially to increase the production of middledistillate and to improve hydrodesulfurization (HDS),hydrodenitrogenation (HDN), hydrodeasphaltenization (HDA's), andhydrodemetallization (HDM) conversions.

This invention comprises a catalyst with physical, chemical and texturalproperties that is primarily used in hydrotreating of heavy crude oilsand residues increasing the production of middle distillates.

Finally, with the present invention a catalyst is obtained for usemainly in the third bed of a fixed bed reactor for hydrotreating heavycrude oils and residues, with hydrogenating power, moderate to lowacidity, in addition it has good activity, stability and minimumdeactivation in long time-on-stream.

BRIEF DESCRIPTIONS OF THE DRAWINGS

In order to have a better understanding of the evaluation of thecatalysts presented in the examples of the present invention, usedmainly in the last bed of a multi-bed reactor system or a seriesreactors for hydrotreating heavy crude oils and residues reference ismade to the following Figures:

FIG. 1 is a schematic representation of the micro-reactor used toevaluate the cumene hydrocracking reaction over the catalysts obtainedby the present invention;

FIG. 2 shows the reaction rate of cumene hydrocracking;

FIG. 3 shows the catalyst evaluation methodology of the presentinvention at microplant scale with light crude feed;

FIG. 4 is a representation of the microplant used in the evaluation ofthe catalysts obtained by the present invention;

FIG. 5 shows hydrodenitrogenation conversion at time-on-stream of 120 h(Example 1);

FIG. 6 shows hydrodesulfurization conversion at time-on-stream of 120 h(Example 1);

FIG. 7 depicts hydrodemetallization conversion at time-on-stream of 120h (Example 1);

FIG. 8 depicts hydrodeasphaltenization conversion at time-on-stream of120 h (Example 1);

FIG. 9 depicts hydrodenitrogenation conversion at time-on-stream of 200h (Example 2);

FIG. 10 depicts hydrodesulfurization conversion at time-on-stream of 200h (Example 2);

FIG. 11 depicts hydrodemetallization conversion at time-on-stream of 200h (Example 2);

FIG. 12 depicts hydrodenitrogenation conversion at time-on-stream of 200h (Example 2);

FIG. 13 shows API Gravity of the product at time-on-stream of 200 h(Example 2);

FIG. 14 shows product yields at time-on-stream of 200 h (Example 2);

FIG. 15 shows a schematic representation of the pilot plant used in theevaluation of the catalysts obtained by the present invention;

FIG. 16 shows hydrotreating conversions at time-on-stream of 432 h(Example 3);

FIG. 17 shows API Gravity of product at time-on-stream of 432 h (Example3);

FIG. 18 shows product yields at temperatures of 360, 370, and 380° C.,at time-on-stream of 32 h;

FIG. 19 shows a multi-bed system in a fixed bed reactor (Example 4);

FIG. 20 shows hydrotreating conversions (hydrodesulfurization,hydrodenitrogenation, hydrodemetallization, hydrodeasphaltenization) attemperatures of 360, 380, 400, 410, and 380° C., at time-on-stream of292 h (Example 4);

FIG. 21 shows API gravity of the product at temperatures of 360, 380,400, 410 and, 380° C., at time-on-stream of 292 h (Example 4); and

FIG. 22 shows product yields at temperatures of 360, 380, 400, 410, and380° C. at time-on-stream of 292 h (Example 4).

DETAILED DESCRIPTION OF THE INVENTION

Hydrodemetallization catalysts must have large pore diameters and porevolume to provide a high storage capacity for metals.

After the hydrodemetallization catalyst, there must follow a catalystfor hydrodemetallization/hydrodesulfurization reactions in order toobtain greater reduction of metals and some sulfur reduction in theoriginal feed. The pore size distribution of this catalyst should bedivided into two ranges, large pore diameters to remove metals, andintermediate pore diameters for removing refractory sulfur compounds.

A third catalyst or groups of catalysts are the catalysts forhydrodesulfurization/hydrocracking that can be placed after thehydrodemetallization catalyst or after thehydrodemetallization/hydrodesulfurization catalysts. The main propertiesof these catalysts are large specific surface area and high reactionrate in hydrodesulfurization, hydrocracking or hydrodenitrogenation

The present invention involves the use of metals of groups VIB and VIIIof the periodic table supported on composite mesoporous materials,molecular sieves, alumina, and adding additives of Groups IVA and VA.

Recently a new family of mesoporous materials of silica have beendiscovered called SBA-15, similar to the MCM-41 but with a considerablylarger pore wall thickness (3-6 nm). These materials are synthesizedusing an organic surfactant, which is commercially cheap, available andbiodegradable. Around this material, the inorganic silicate molecules,typically present in the reaction mixture with acidic pHs≦1, areorganized. When the organic component is extracted, the remaininginorganic solid has a hexagonal arrangement with pore diameters betweenof 6 to 12 nm, specific surface area around 600 to 1000 m²/g and porevolume of 0.8 to 1.3 cm³/g.

SBA-15 is chemically inert because it is formed by pure SiO₂, limitingits application as a catalyst or catalyst support. However, the physicaland chemical properties of the surface can be modified by depositing onthe surface metal oxides of group IIIA such as aluminum or group IV liketitanium or zirconium, etc. This modifies the surface acidity andprovides new chemical surface properties, while preserving the texturalproperties of this material making it more attractive as a support forcatalysts.

Molecular sieves, which can be zeolites, contain in their structuresilicon, aluminum, sodium, hydrogen, and oxygen.

Recently, ultrastable materials MSAMS-2 have been obtained using SBA-15as a template or rigid structure-directing agent. Nuclear magneticresonance (NMR) confirmed the increment in the condensation of silanolgroups by increasing the ratio (SiO₂)⁴/(SiO₂)³ [Q⁴/Q³]. The hydrothermalstability depends on the formation of zeolite subunits and the insertionof structural atoms of aluminum in the mesoporous material. Furthermorethere is an increment in wall thickness.

The physical mixture of alumina and zeolite is an excellent support forNiMoS catalysts, which show high activity for hydrodesulfurization (HDS)of refractory sulfur species. The catalyst also has high resistance topoisoning by hydrogen sulfide (H2S). However, the excessive cracking ofthe feed and deactivation of the zeolite are mainly due to the highacidity of these materials. Strong acidity in HDS catalysts improveshydrodesulfurization of refractory sulfur compounds, substituteddibenzothiophenes, with alkyl groups at positions 4 and 6, minimizingsteric effects and increasing the hydrogenation of the aromatic rings inthe neighborhood of the sulfur. Besides, zeolites as strong acidsupports appear to increase the release of hydrogen sulfide in thesulfided catalysts by weakening the metal-sulfur bond; this functioncauses a high tolerance for H₂S. The alumina-zeolite supports in NiMocatalysts show high hydrodesulfurization activity in refractorycompounds in the presence of 1.67% H₂S in H₂. Pure zeolite canhydrodesulfurize dibenzothiophene (DBT) through the direct eliminationof the sulfur atoms or by the hydrodesulfurization-hydrogenation route.Therefore, the cracking capability of the alumina-zeolite supports inthe supported catalysts is due to effect of the zeolite.

A balance between acidity, porosity of the substrate, and the activephases must be found. According to the present invention, the mesoporouscomposites, which involve mechanical mixtures of different materials,provide this balance.

The hydrocracking catalyst of the present invention comprises at least ametal of groups VIB and VIIIB of the periodic table of elementssupported by composites of mesoporous materials, molecular sieves andalumina, containing additives of the groups IVA and VA. This catalysthas suitable hydrogenating ability and moderate acidity, as well as anaverage pore diameter of 6.0 to 15.0 nm and a percentage of pores withdiameters ranged 5-50 nm between 74.0-85.0%, for carrying out thehydrocracking of a hydrocarbon feedstock, such as, asphaltenes andremoving sulfur, nitrogen and metals compounds from asphaltenicmolecules, which allows the catalyst to increase the conversion of allreactions (HDS, HDM, HDN, HDA's) when the reaction temperature increasefrom 360 to 410° C. Additionally the API gravity of the feedstock willincrease from the original value of 4.4° API to 12.6° API and 19.4° APIin the products at 360 and 410° C., respectively, namely, increments of8.2 to 15° API.

The catalyst support of the present invention is a composite of aluminamolecular sieve mesoporous material. Preferably, the composite supportis formed of a mechanical mixture boehmite, zeolite and SBA-15, whichcan be used in a ratio in the range of 60 to 85, 5 to 15, 10 to 35, eachratio in percent by weight, respectively. An especially preferred ratiois 70:10:20 wt %. The support can be prepared, for example, bymechanical blending a commercial boehmite (Catapal C-1), zeolite andSBA-15, peptizing the mixture with nitric acid (10 vol %). The peptizedmixture is then extruded to a size of 1/16 in, dried at room temperaturefor 12 hours; then dried in an oven at 120° C. for 3 hours, and, thencalcined at 550° C. for 4 hours (heating at 2° C./min).

Aluminas in addition to boehmite. Include aluminum precursor salts asanhydrous AlCl₃ [Ryoo R, et al. J. Chem. Commun (1997) 2225], aluminumisopropoxide in non-aqueous solutions [Bagshaw, S. A. et al: Chem.Commun. (1996) 2209] or sodium aluminate in aqueous solution [Hamdam H.et al. J. Chem. Soc. Faraday Trans. 92 (1996) 2311. Suitable zeolites(crystalline molecular sieves) include Y zeolite [Kunisada, N. et al.Appl. Catal. 269 (2004) 43. USY zeolite, ZSM5 [Kloestra, et al. Chem.Commun. (1997) 2281]. All of the foregoing articles are herebyincorporated by reference in their entirety.

The composite mesoporous support of the present invention can beutilized with any suitable metal of Group VI B and Group VIII of theperiodic table. Suitable Group VI B metals include molybdenum, tungsten,[P. Rayo, et al. Petroleum Science and Technology 25 (2007) 215; P.Rayo, et al. Fuel 100 (2012) 34; Mohan S. Rana, et al. Fuel 86 (2007)1254; Mohan S. Rana, et al. Catal. Today 107-108 (2005) 346, Mohan S.Rana, et al. Catal. Today 109 (2005) 61; Jorge Ramirez, et al. Catal.Today 109 (2005) 54, Samir K. Maity, et al. Catal. Today 109 (2005) 61;F. Trejo, et al. Fuel 100 (2012) 163; B. Caloch, et al. Catal Today 98(2004) 91]. Suitable Group VIII metals include nickel, cobalt [P. Rayo,et al. Petroleum Science and Technology 25 (2007) 215; P. Rayo, et al.Fuel 100 (2012) 34; Mohan S. Rana, et al. Fuel 86 (2007) 1254; Mohan S.Rana, et al. Catal. Today 107-108 (2005) 346, Mohan S. Rana, et al.Catal. Today 109 (2005) 61; Jorge Ramirez, et al. Catal. Today 109(2005) 54, Samir K. Maity, et al. Catal. Today 109 (2005) 61; F. Trejo,et al. Fuel 100 (2012) 163; B. Caloch, et al. Catal Today 98 (2004) 91].All of the foregoing articles are hereby incorporated by reference intheir entirety.

Additives including metals of Group IVA and Group VA may be used as Si,and P, etc. [P. Rayo, et al. Petroleum Science and Technology 25 (2007)215; Samir K. Maity, et al. Catal. Today 109 (2005) 61; Mohan S. Rana,et al. Appl. Catal. 425-426 (2012) 1]. All of the foregoing articles arehereby incorporated by reference in their entirety.

For example, the composite mesoporous support of the present inventionmay be impregnated with a solution of ammonium heptamolybdate and nickelnitrate to obtain a concentration of Mo and Ni of 10 and 2.6 wt %,respectively and extruded. The extrudates may be allowed at rest for 12hours at room temperature, then dried at 120° C. for 3 hours andcalcined at 450° C. for 4 hours.

The catalyst of the present invention has, for example, a low tomoderate total acidity at 100° C., equivalent to 180 to 360 micromolesof pyridine per gram of catalyst, a specific surface area of 150-300m²/g, an average pore diameter of 6.0 to 15.0 nm, and a pore volume of0.2 to 0.7 cm³/g. Likewise, the present catalyst may have the followingpore distribution: less than 20% of its pore volume of pores having adiameter of 5 nm or less, 70 to 85% of its pore volume of pores having adiameter of 5 to 50 nm, and less than 5% of its pore volume in poreswith diameter greater than 50 nm. In one embodiment, the catalyst has20% of its pore volume having a pore diameter of 0 to 5 nm.

The catalyst of the present invention can be “tailored” or designed foruse in the last bed of a multi-bed system, particularly where the feedstream flows downwards. The contact area between the catalyst and feedis improved in downflow mode. By using feed distributors at the top ofthe reactor, the liquid distribution over the catalyst bed is enhanced.The feed that the catalyst processes in this invention contains loweramounts of metals and it is lighter than the stream which is fed to thefirst bed.

The catalyst developed in this invention is dual-functional, and behavesdifferently depending on the reaction temperature. In this regard, thereare two important zones of reaction, one at temperatures below 400° C.(360-380° C.) and other at temperatures greater than or equal to 400° C.In the zone of 360-380° C. the catalyst has hydrogenating power and lowto moderate acidity for breaking high molecular weight molecules.However, when operating at temperatures above 400° C., where cracking ismainly thermal, the catalyst has a high percentage of pores withdiameters in the range of 10-50 nm to allow the reactions ofhydrodemetallization, hydrodeasphaltenization, and hydrodesulphurizationwhere asphaltenic sulfur is present.

The catalyst of the present invention is particularly useful in thethird bed (hydrodesulfurization/hydrocracking) of a reactor or a systemof fixed bed reactors for hydrotreating heavy crude oils and residues,and can be designed to increase the production of distillates in thetemperature range of 204° C. to 538° C., and also for decreasing theproduction of vacuum residue (538° C.+). The feedstock to be processedcontains low amounts of metals and is lighter than the feedstock whichis fed into the first bed. This catalyst has high hydrogenating power,low to moderate acidity and intermediate pore diameter (higherpercentage of pores in the range of 10-50 nm) for removing sulfurcompounds from asphaltenic molecules. This feedstock is also constitutedof heavy hydrocarbons, asphaltenic compounds, and asphaltenic sulfur,nitrogen, and metals (nickel and vanadium). The present inventionrelates to a synthesis of catalysts for the hydrotreating of heavy crudeoils and residues, coming from previous hydrotreating in catalytic beds.

Thus, the present invention is preferably directed to a catalyst to beused in the third bed (hydrodesulfurization/hydrocracking) in a fixedbed reactor in a process for hydrotreating of heavy crude oils andresidues, which were treated in a previous catalytic bed(s). Thecatalysts of the present invention are used to increase production ofdistillates with boiling temperatures among 204-538° C., and decreaseproduction of vacuum residue (538° C.+), and primarily reduce thecontent of sulfur, while simultaneously other reactions are performedsuch as HDM, HDN, and the HDA's, to produce a light crude oil andincrease the production of the hydrocarbon fraction in the range of<204° C. (gasoline).

The present invention constitutes an improvement over previous catalystsystems because the present catalyst has particular use in the last bed(hydrodesulfurization/hydrocracking) of a multi-bed system followinghydrodemetallization and/or hydrodemetallization/hydrodesulfurizationand can increase the production of distillates with a boiling range from204 to 538° C., decrease the production of vacuum residue (538° C.+) andincrease the gasoline fraction (<204° C.). The product of the last bed,which is a feed for further processing, such as reforming, containslower amounts of metals and is lighter than the stream which is fed tothe first bed because in the preparation of the supports for thecatalyst of the last bed, elements of Groups III A and IV A formingmesoporous composites can be used resulting in a catalyst having thefeatures of: a low to moderate total acidity at 100° C., 180 to 360micromoles of pyridine per gram of catalyst, a specific surface area of150-300 m²/g, an average pore diameter of 6.0 to 15.0 nm, a pore volumeof 0.2 0.7 cm³/g, and the percentage of pores in the range of 5-50 nmbetween 74-85% to carry out the hydrocracking of asphaltenes and toremove sulfur, nitrogen, and metals compounds from asphaltenicmolecules, with low metal content 1-5 wt % for elements of group VIIIBand 3-15 wt % of group VIB.

As indicated, temperature conditions used for hydrocracking in thehydrocracking process of the present invention determine the behavior ofthe catalyst. Thus, one behavior at temperature less than 400° C.(360-380° C.) and another behavior at temperature ≧ to 400° C. If thehydrocracking reaction or last bed of a multi-bed catalyst operation isconducted at a temperature between 360 and 380° C., the catalyst hashydrogenating ability and low to moderate acidity to perform thecracking of molecules with high molecular weight. However, if atemperature ≧ to 400° C. is used, the cracking is primarily thermal.Likewise, if the purpose is to assure the enhancement in the conversionof all the reactions (HDM, HDN, HAD's) temperature should be increased,for example, from 360 to 410° C.

The process for hydrocracking of heavy crude oil or residues can becarried out in a multistage or multizone fixed bed reactor. The initialstage or stages include have as their purpose the reduction of thecontent of impurities such as organometallic, sulfur and nitrogencompounds, and on the other hand reducing viscosity and increasing theAPI gravity of the feedstock, prior to the last stage or zone, where theSBA-15 supported hydrocracking catalyst of the present invention isutilized in accordance with the present invention. Such multi-stagetreatment of heavy crude, including process conditions and catalystsused in the first, intermediate and final stage(s) or zone(s) forcatalytic treatment of heavy crude oil is discussed in detail in U.S.published Application No. 2013/0056394 to Ancheyta Juarez et al, thedisclosure of which is hereby incorporated by reference in its entirety.

Thus, the initial and/or intermediate stage or stages include a catalystto hydrodemetallize or hydrodemetallize/hydrodesulfurize the heavy crudeoil or residue using a catalyst having a support different from the laststage or zone in which the SBA-15-supported catalyst is used. Thecatalyst in the pre-hydrocracking stage or stages can be a NiMo onalumina, for example. The demetallized, desulfurized heavy crude oilfrom such first and/or intermediate stages is fed to the last stage(s)or zone(s), where it contacts a NiMo-impregnated alumina-molecularsieve-mesoporous silica material of the present invention. Thus, thefeed to the last stage may be characterized as a demetallized,desulfurized heavy crude or residue.

The present cracking catalyst can be used in the last bed of a multi-bedsystem to improve the production of intermediate distillates from heavycrude oils or residues so as to increase the API gravity from 4.4° inthe feedstock to 12.6° and 19.4° in the product at 360 and 410° C.,respectively, i.e. increments of 8.2° to 15° API. Likewise, it can bedesigned to improve the production of intermediate distillates to obtainan increase in the yield of:

-   -   a) the 343-454° C. fraction (straight run heavy gasoil and light        vacuum gasoil) from 2 to 10.5 wt %;    -   b) the 204-274° C. fraction (Jet fuel) from 1.4 to 8.5 wt %;    -   c) the 274-316° C. fraction (kerosene) from 1.3 to 5.1 wt %;    -   d) the <204° C. fraction (gasoline) from 0.4 to 3.4 wt %;    -   e) the 316-343° C. fraction (straight run heavy gasoil) from 0.8        to 3.2 wt %;    -   f) the 454-538° C. fraction (heavy vacuum gasoil) from 0.8 to        2.3 wt %; and    -   g) the vacuum residue (>538° C.) depending on the reaction        temperature, rendering 6.74% at 360° C. and 33% at 410° C.

The feedstocks to be treated with the catalyst of the present inventionlocated in the third bed of a multi-bed system could contain from asmall amount of metal up to 700 wppm of the total amount of nickel andvanadium, up to 10 wt % of asphaltenes, and sulfur content within therange from 0.5 to 5 wt %.

The following examples describe how to obtain the catalyst withproperties suitable for use primarily in the third bed for hydrotreatingheavy crude oils and residues.

EXAMPLES

The following examples are presented to illustrate the performance ofthe catalysts of the present invention and their use in thehydrotreating of heavy crude oils and residues. These examples shouldnot be considered as limiting of the present invention, because theysimply illustrate different procedures for the preparation of thesupport, the application of the catalyst with this type of feedstock, aswell as the operating conditions.

Example 1

In the preparation of the supports for the prototype of this Example 1was used commercial boehmite, tetraethyl orthosilicate (TEOS) fromAldrich, and mesoporous material (SBA-15) synthesized in the laboratory.

For the preparation of the supports of the present example we usedboehmite as binder.

For the synthesis of support for prototype 1 (Prot-1), boehmite was usedas starting material wherein to a portion of the total boehmite (10%)used as a binder was added the required amount of nitric acid (HNO₃) at10 wt % to peptize it, then gradually the rest of the boehmite (90 wt %)and deionized water were added, until achieving a homogeneous paste withthe right consistency to extrude and get extrudates of 1/10 inch indiameter. The extrudates were aged from 12 to 18 h, dried at 100-120° C.for 2-6 h, and subsequently calcined using a temperature ramp of 2°C./minute up to 500-550° C., maintaining the last temperature for 4hours to obtain an alumina support in its gamma phase.

For the synthesis of the support for prototype 2 (Prot-2) similarprocedures as for the synthesis of Prot-1 were applied, with thedifference that to 90% by weight of the boehmite the required amount oftetraethyl orthosilicate (TEOS) was added to obtain 5 wt % of silicon onthe calcined material (SiO₂—Al₂O₃).

In the synthesis of the support of prototype 3 (Prot-3), to theγ-alumina support obtained in the synthesis of Prot-1, the requiredamount of TEOS was added by wetness incipient method to obtain 5 wt % ofsilicon. The extrudates were aged from 12 to 18 h, dried at 100-120° C.from 2 to 6 h, and subsequently calcined with a temperature ramp of 2°C./minute up to 500-550° C., and maintaining at this temperature for 4hours to obtain a support of SiO₂/Al₂O₃.

In the synthesis of the support of prototype 4 (Prot-4), first SBA-15was synthesized according to the procedure published by Zhao et al.(1998) described in Dongyuan Zhao, et al. (1998). “Triblock CopolymerSyntheses of Mesoporous Silica with Periodic 50 to 300 Angstrom Pores”.Science 279 (5350): 548. In a glass reactor 8 g of Pluronic 123(Aldrich) were dissolved in 160 g of acid (HCl) 2N [82 mL of HCl(Fermont, purity 37%) in a 500 mL volumetric flask with constantstirring at a temperature of 40° C. during 3 h. Maintaining constantboth temperature and agitation 17.6 g of TEOS (Aldrich, purity 99%) wereadded dropwise, afterwards 40 mL of deionized water were added dropwise,the system was capped and closed. The reaction was carried out at 40° C.with constant stirring during 20 h.

The reaction product was transferred to a Teflon bottle, which wasperfectly closed, and was put into an oven at 100° C. during 48 h. Theproduct was cooled, filtered under vacuum and washed with about 3 litersof water to remove excess of surfactant. The solid obtained was placedin a desiccator and then calcined at 500° C. during 6 h using an initialheating rate of 0.5° C./minute to obtain the SBA-15.

Later a support was prepared with 80/20 wt % ratio of Al₂O₃-SBA-15 bymixing mechanically boehmite Catapal C-1 and SBA-15. This solid mixturewas peptized with nitric acid in concentration of 10 vol %, and wasextruded in the form of cylinders of 1.59 mm diameter and length in therange of 2 to 7 mm, dried at room temperature during 12 h followed bydrying in an oven at 120° C. during 3 h, then calcined at 550° C. during4 h using an initial heating rate of 2° C./minute.

The last four supports were impregnated with a solution of ammoniumheptamolybdate and nickel nitrate to obtain a concentration of Mo and Niof 10 and 2.6 wt %, respectively, the extrudates were aged during 12hours at room temperature, then dried at 120° C. during 3 h and calcinedat 450° C. during 4 h using a heating rate of 2° C./minute, obtainingthe corresponding prototypes Prot-1, Prot-2, Prot-3, and Prot-4.

The textural properties of these four prototypes (Prot-1, Prot-2,Prot-3, and Prot-4) are shown in Table 1.

TABLE 1 Textural properties of the prototypes of Example 1 PropertiesProt-1 Prot-2 Prot-3 Prot-4 SSA, m²/g 162 189 151 276 PV, cm³/g 0.4 0.40.3 0.5 APD, nm 9.2 7.8 8.3 7.4 PVD, %  <5, nm 13.6 23.3 21.4 20.8 5-50,nm 84.8 74.2 75.6 76.6 >50, nm 1.6 2.6 3.0 2.6 Mo, wt % 8.0 6.5 6.5 6.0Ni, wt % 2.6 3.0 3.5 3.0 SSA = Specific surface area, PV = Pore Volume,APD = Average pore diameter, PVD = Pore volume distribution.

On the other hand, a micro-reactor (FIG. 1) operating in a differentialmode was used to measure the hydrocracking rate of cumene, which gives arelative measure of the acidity of these prototypes, using as reactionmodel the hydrocracking of cumene at reaction conditions of 400° C. andatmospheric pressure.

The results of hydrocracking rate of cumene for each prototype are shownin FIG. 2. This figure shows that the prototype Prot-4, which containsSBA-15 as silicon source, has the highest acidity. Activity of theseprototypes in the hydrocracking of cumene was:Prot-4>>>Prot-2>Prot-3>Prot-1.

FIG. 3 shows the methodology used in the microplant scale evaluation ofthe catalysts of the present invention. The step A consists of loadingthe reactor with a uniform mixture of 10 mL of catalyst and 10 mL ofsilicon carbide (SiC) as inert material. The step B corresponds tohermeticity test at a pressure 10% greater than the operating pressure(P=1.1P_(op)). The Step C concerns the sulfidation of the catalyst,which was carried out with straight run gas oil from atmosphericdistillation of crude oil, doped with dimethyl disulfide (DMDS) toobtain 1.0 wt % sulfur, at the following conditions: temperature of 320°C., pressure of 28 kg/cm², space velocity (LHSV) of 2.0 h⁻¹,hydrogen/hydrocarbon ratio of 2000 ft³/bbl. Step D corresponds to theoperation phase, that is performed with a feed into the reactor inupflow, the feedstock used is light crude oil 21.5° API.

Operating conditions in step D are the following: temperature of 380°C., pressure of 70 kg/cm², hydrogen/hydrocarbon ratio of 5,000 ft³/bbl,and LHSV of 1.0 LHSV h⁻¹. In the step D the reaction is carried outduring 120 h of time-on-stream and product samples are recovered each 12hours. Finally, in step E, analysis of liquid products obtained isperformed.

The conditions for evaluating microplant level catalysts are presentedin Table 2.

TABLE 2 Operating conditions for catalyst evaluation at microplant levelVariables Temperature, ° C. 380 Pressure, kg/cm² 70 H₂ flow, L/h 12.4Feedstock flow, mL/h 10 LHSV, h⁻¹ 1.0 H₂/HC ratio, ft³/bbl 5000Operating mode Upflow Time-on-stream, h 120 y 200 Catalyst volume, mL 10

FIG. 4 is a schematic representation of the equipment used to evaluateat microplant level each one of the catalysts obtained in the Examplesof the present invention.

For the evaluation at microplant level of each prototype a light crudeoil was used as feedstock, which contains 151 wppm of metals (Ni+V). Thefeedstock properties are shown in Table 3.

TABLE 3 Physical and chemical properties of the feedstock used toevaluate catalysts of example 1 at microplant scale Properties Densityat 20° C., g/mL 0.880 API gravity 37.1 Conradson carbon, wt % 5.4Nitrogen content, wt % 0.18 Sulfur content, wt % 2.2 Metals, wppm Ni26.2 V 124.8 (Ni + V) 151.0 Asphaltenes, nC₇ insolubles, wt % 8.43

The behavior of the prototypes in the HDN reaction is shown in FIG. 5,where Prot-4 prototype presented the highest activity and stability withan initial conversion of 42% at 6 h of reaction and HDN conversion of27% at 120 h of reaction. Moreover, prototype Prot-1 was the one thatdeactivated faster. The order of activity of prototypes in the HDNreaction was the same as the acidity of the prototypes observed in thecumene hydrocracking reaction.

FIG. 6 shows the behavior of HDS reaction, where it is observed thatalthough prototype Prot-1 has a higher initial activity, 81.4% HDS, itsstability drops down 30% (end HDS 51.4%). Prototypes Prot-2, Prot-3, andProt-4 with initial HDS conversions of 61.3, 57.0, and 61.5%,respectively, although they present a lower initial activity comparedwith Prot-1, they show a better stability, because the activity of onlydiminishes from 15 to 21%.

FIG. 7 shows the behavior of the four prototypes in the HDM reaction,where it is observed that Prot-1 presents a HDM deactivation of about46% during 120 h time-on-stream. Regarding prototypes Prot-2 and Prot-3,the observed deactivation at the same operation time is 26 and 19%,respectively. Moreover, prototype Prot-4 is the one with the lowest HDMinitial activity (45%) compared with the prototypes Prot-1, Prot-2, andProt-3, however, its stability is higher during 120 h reactiondecreasing its activity only 8%.

The performance of the four prototypes on HDA's reaction is presented inFIG. 8, where it is observed that all prototypes have a moderatedeactivation during 120 hours of reaction, prototype Prot-4 presentedthe lowest deactivation, followed by Prot-2, and finally Prot-3.

Example 2

In this example the same commercial boehmite Catapal C-1 and SBA-15considered in Example 1 were used, besides zeolite Y (CBV-720) of theZeolyst brand.

For the synthesis of support of prototype Prot-5, SBA-15, synthesizedpreviously in Example 1, was modified with a solution of aluminumnitrate by the incipient wetness method, to obtain a support with 20 wt% of Al. This solid mixture was peptized with nitric acid at 10 vol %concentration, then was extruded to obtain extrudates of 1/16 inch (1.59mm) size, dried at room temperature (±20° C.) during 12, afterwards wasput into an oven at 120° C. during 3 h, and finally calcined at 550° C.during 4 h (2° C./min).

For the synthesis of support of prototype Prot-6, a support withAl₂O₃-SBA-15-zeolite ratio of (70-20-10 wt %, respectively) was preparedby a mechanically mixing a mixture of commercial boehmite (Catapal C-1),SBA-15, and zeolite. This solid mixture was peptized with nitric acid of10 vol % concentration, then was extruded to obtain extrudates of 1/16inch size, after was dried at room temperature (±20° C.) during 12 h,then was put into an oven at 120° C. during 3 h, finally was calcined at550° C. during 4 h (2° C./min). The supports were impregnated with Moand Ni with the same route and the same content as in Example 1. Thecatalysts obtained in this Example 2 are the prototypes Prot-5 andProt-6.

Textural properties of these prototypes are shown in Table 4. This tablealso includes the properties of Prot-4 of Example 1.

TABLE 4 Textural properties of the catalysts of Example 2 PropertiesProt-4 Prot-5 Prot-6 Density, g/mL 0.70 0.66 0.71 SSA, m²/g 276 220 331PV, mL/g 0.5 0.4 0.5 APD, nm 7.4 7.7 6.6 PVD, %  <5, nm 20.8 18.7 205-50, nm 76.6 79.8 78.7 >50, nm 2.6 1.5 1.3 Mo, wt % 6 6 7 Ni, wt % 3 32.2 SSA = Specific surface area, PV = Pore volume, APD = Average porediameter, PVD = Pore volume distribution.

For Evaluating of prototypes of this Example 2 the same microplant (FIG.4) as in Example 1 was used, during time-on-stream of 200 h using heavycrude oil as feedstock. Heavy crude properties are presented in Table 5.Evaluation conditions are the same used in Example 1.

TABLE 5 Physical and chemical properties of heavy crude oil used toevaluate the catalysts of Example 2 at microplant scale. PropertiesDensity at 20° C., g/mL 0.925 API Gravity 21.5 Conradson carbon, wt %10.9 Nitrogen content, wt % 0.3 Sulfur content, wt % 3.5 Metals, wppm Ni49.5 V 273.0 (Ni + V) 322.5 Asphaltenes, nC₇ insolubles, wt % 12.7

The results of the hydrotreating reactions are described as following.

FIG. 9 shows the behavior of prototypes Prot-4, Prot-5, and Prot-6 onHDN reaction, where it is observed that Prot-4 has higher initialactivity and stability during time-on-stream of 200 h in comparison withprototypes Prot-5 and Prot-6. The behavior of Prot-5 and Prot-6 in theHDN reaction is similar, because these prototypes present similardeactivation, 11.5 and 7.5%, respectively.

FIG. 10 shows the HDS activity of the three prototypes Prot-4, Prot-5,and Prot-6, which have the following initial activity trendProt-4˜Prot-5>Prot-6, although the decrease in activity duringtime-on-stream follows the trend: Prot-5 (34.5%)>Prot-4 (26.8%)>Prot-6(11%).

The behavior of HDM (FIG. 11) is similar to that shown for HDN (FIG. 9).The prototype that displays greater HDM activity is prototype Prot-4with an initial activity of 52.4% and a final activity of 43.9% attime-on-stream of 200 h giving for this prototype a conversion drop of8.5%, followed by that observed for Prot-5 with a drop in conversion of18.3%. It is noteworthy that although prototype Prot-6 had the lowestinitial activity (25.3%) its drop in conversion was only 2.1%.

Regarding the HDA's reaction presented in FIG. 12, the deactivationpresents the following trend Prot-4>Prot-6>Prot-5. Therefore, inaccordance with the initial activities of each catalyst, the finalactivity after 200 h of time-on-stream is: Prot-5>Prot 4>Prot-6.

With respect to the API gravity of the product, shown in FIG. 13,prototype Prot-4 produced lighter products (high API gravity) followedby prototype Prot-6 having an average difference in these prototypes of±3° API gravity. Prototype Prot-5, which initially produced a high APIgravity of 24.8° API in products, after 200 h of time-on-stream, itsproduct reaches the value of 21.5 API gravity, which is the same as thatof the heavy crude oil feedstock.

FIG. 14 shows the difference of yield between the feedstock andfractions of heavy crude oil: Gasoline (<204° C.), jet fuel (204-274°C.), middle distillates (274-538° C.), and vacuum residue (>538° C.),where Prot-6 showed the higher vacuum residue conversion, higher yieldto middle distillates, higher yield to jet fuel, and higher yield to thegasoline fraction, followed by Prot-5 and finally Prot-4, having anincrease in yield of gasoline fraction with respect to the feedstock of2.5, 1.8, and 1.5% for prototypes Prot-6, Prot-5, and Prot-4,respectively.

Example 3

The activity of the catalysts of the present invention was alsoevaluated in a pilot plant. FIG. 15 presents a flow chart thatillustrates the pilot plant.

The catalytic evaluation of this example was carried out in a pilotplant scale with prototype Prot-6 (71.86 g). The synthesis of thiscatalytic prototype is described in the Example 2 of the presentinvention. The uploading of this prototype to the reactor was performedas follows: 100 mL of Prot-6 with 50 mL of inert material (siliconcarbide SiC, 30 mesh), 5 beds each one containing 10 mL of inert and 20mL of Prot-6 were placed in the reactor. The operating temperatures were360, 370, and 380° C. each one was maintained for 144 hours, thetime-on-stream was 432 h. Heavy crude oil was used as feedstock. Theoperating conditions are shown in Table 6. The heavy crude oilproperties are the same as in Example 2 (Table 5).

TABLE 6 Operating conditions at pilot plant scale for the evaluation ofcatalyst from Example 3 Variables Temperature, ° C. 360, 370 y 380Pressure, kg/cm² 100 H₂ flow, L/h 47.9 Feedstock flow, mL/h 50 LHSV, h⁻¹0.5 H₂/HC ratio, ft³/bbl 5000 Operating mode Downflow Time-on-stream, h432 Catalyst volume, mL 100 Extrudate diameter, mm 1-3 Extrudate length,mm 2-7

FIG. 16 shows the results for hydrotreating reactions with prototypeProt-6 at different reaction temperatures, 360, 370, and 380° C. at 432h of time-on-stream. It is observed that as the reaction temperatureincreases, the activity of HDS, HDN HDM, and HDA's also increases, itcan also be seen that the conversion levels obtained in each reactionare as follows: HDS (60%)>HDN (38%)>HDM (36%), and HDA's (28%) whereinthe number in parenthesis is the conversion at 380° C. A similarbehavior is also observed for the API gravity of the product; when thereaction temperature increases, the API gravity also increased, thesevalues are illustrated in FIG. 17, which shows that at temperatures of360, 370, and 380° C., the API gravity values obtained are 26.6, 26.7,and 27.3° API. The values of API gravity at each reaction temperaturewith respect to heavy crude oil (21.5° API) were: 5.1° API (360° C.),5.2° API (370° C.), and 5.8° API (380° C.).

The FIG. 18 shows the values of the difference of products of eachfraction with respect to the feedstock.

By increasing the reaction temperature from 360 to 380° C., there is asignificant reduction of the heavy fraction (>538° C.), which decreases−6.6%, −7.6%, and −9.2% at the reaction temperatures of 360 to 370, and380° C., respectively. The yield of the other fractions with boilingpoints lower than 538° C. increases with the reaction temperature, thefraction which showed the greater benefit in yield was the jet fuel with2.5, 2.3, and 2.7% at temperatures of 360, 370, and 380° C.,respectively.

Example 4

For this example 4, the prototype Prot-6 (60 mL) was placed in the thirdcatalytic bed of fixed bed reactor, the catalytic beds 1 and 2 (45 mLeach) are NiMo catalysts supported on alumina (FIG. 19).

This evaluation was performed at pilot plant scale (FIG. 15, Example 3)at a pressure of 100 kg/cm², space velocity (LHSV) of 0.25 h⁻¹,temperatures of 360° C. (100 h), 380° C. (48 h), 400° C. (48 h), 410° C.(48 h), and 380° C. (48 h) for a total time-on-stream of 292 h. Theoperating conditions and properties of the feedstock are reported inTables 8 and 9, respectively.

TABLE 8 Operating conditions at pilot plant scale in a multistage system(Example 4) Pilot plant scale Variables Multistage system Temperature, °C. 360, 380, 400, 410 y 380 Pressure, kg/cm² 100 H₂ flow, L/h 47.9Feedstock flow, mL/h 50 LHSV, h⁻¹ 0.25 H₂/HC ratio, ft³/bbl 5000Operating mode Downflow Time-on-stream, h 292 Volume of catalyst, mL 150Extrudate diameter, mm 1-3 Extrudate length, mm 2-7

TABLE 9 Physical and chemical properties of the feedstock of example 4Residue from Extra heavy Variables crude oil Density at 20° C., g/mL1.038 API Gravity 4.4 Conradson carbon, wt % 21.48 Nitrogen, wt % 0.6003Total sulfur, wt % 6.24 Metals, wppm Ni 119 V 572.4 (Ni + V) 691.4Asphaltenes, insolubles in nC₇, wt % 25.19

The feedstock entering the first catalytic bed is a residue obtainedfrom extra heavy crude oil. It is noteworthy that when the feedstockreaches the third catalytic bed where the Prot-6 is located, the metalcontent is reduced at values similar to those in a heavy crude.

FIG. 20 shows the variation in the conversion in each HDT reaction whenthe operating temperature in the reactor varies.

It is observed that by increasing the reaction temperature from 360 to410° C. the conversion of all the reactions increases. The order ofactivity of the different reactions is HDS>HDM>HDN>HDA's.

By changing the temperature from 360 to 410° C. the conversions varied51.1-82.6%, 40.3-72.8%, 31.3-50.9%, and 28.9-45.8% for the of HDS, HDM,HDN, and HDA's reactions, respectively.

This indicates that the HDN and HDA's reactions are the most difficultto perform.

When the temperature is returned to 380° C., it is observed a slightdecrease in the level of conversion in all reactions compared with theinitial values observed at 380° C.

The API gravity (FIG. 21) increases with the reaction temperature. Thefeedstock residue has an API gravity of 4.4°. The API gravity in theproduct at each temperature increased as follows 360° C. (8.2° API),380° C. (9.1° API), 400° C. (13.3° API), 410° C. (15° API), and 380° C.(8.1° API). When the temperature is again fixed at 380° C., it isobserved an increase in the API gravity of 8.1°, which is slightly lowerthan the value of 9.1° API observed before operating the reactor at 400°and 410° C. The results indicate that employing Prot-6 catalyst in thethird bed of the reactor allows for a better quality product with 19.4°API at 410° C., which means an increment of 15° API with respect to thefeedstock (4.4° API). The highest increase in API gravity is observedwhen the reactor operating temperature increases from 380 to 400° C.

With respect to products yield, FIG. 22 shows that it increases with thereaction temperature, being higher at 410° C. The increment in the yieldis notably higher in the fraction 343-454° C. (Straight run heavy gasoil and vacuum gasoil), followed by 204-274° C. (Jet fuel), 274-316° C.(Kerosene), <204° C. (Gasoline) and 316-343° C. (Straight run light gasoil), and finally the fraction 454-538° C. (vacuum heavy gas oil).According the information mentioned above the yield of residue (>538°C.) decreases when the reaction temperature increases. The observeddecrease in the vacuum residue (>538° C.) yield is 6.74% at 360° C. and33% at 410° C.

What is claimed is:
 1. A catalyst for hydrocracking of heavy crude oilsand residues to increase the production of intermediate distillatescomprising a catalyst support obtained from boehmite, zeolite Y, andSBA-15 in a molar ratio of 60-85:5-15:10-35, respectively, and wheresaid catalyst has a cylindrical shape with a diameter of 1.59 mm and alength of 2-7 mm and includes 3-15 wt % of a Group VIB metal comprisingmolybdenum as molybdenum oxide or molybdenum sulfide and 1-5 wt % of aGroup VIII metal comprising nickel as nickel oxide or nickel sulfide,said catalyst having a specific surface area of 150-300 m²/g, an averagepore diameter of 6.0 to 15.0 nm, a pore volume of 0.2 to 0.7 cm³/g, anda pore distribution of 20% of pores having a diameter of up to 5 nm, 70to 85% of pores having a diameter of 5 to 50 nm, and less than 5% ofpores having a diameter greater than 50 nm, and a total acidity at 100°C. equivalent to 180 to 360 micromoles of pyridine per gram of catalyst.2. The catalyst of claim 1, wherein the support is prepared bymechanical blending of a boehmite, zeolite and SBA-15, which is peptizedwith nitric acid, extruded, and calcined.
 3. The catalyst of claim 2,wherein the support is impregnated with a solution of ammoniumheptamolybdate and nickel nitrate to obtain a Mo and Ni impregnatedcatalyst.
 4. The catalyst of claim 1, wherein said Mo and said Ni arepresent in a molar ratio of Mo/Ni+Mo=0.3.
 5. A catalyst forhydrocracking heavy crude oils and residues to increase production ofintermediate distillates, wherein said catalyst comprises a catalystsupport obtained from boehmite, zeolite Y, and SBA-15 in a molar ratioof 60-85:5-15;10-35, Mo and Ni, and is prepared by a method of preparinga support by combining boehmite, zeolite Y, and SBA-15 in amounts of60-85 wt %, 5-15 wt % and 10-35 wt %, respectively, peptizing theresulting mixture, drying the mixture and calcining to obtain thesupport, and impregnating said support with a solution of ammoniumheptamolybdate and nickel nitrate, drying the impregnated support, andcalcining to obtain said catalyst containing Mo and Ni, wherein saidcatalyst comprises 3-15 wt % of molybdenum as molybdenum oxide ormolybdenum sulfide and 1-5 wt % of nickel as nickel oxide or nickelsulfide, said catalyst having a specific surface area of 150-300 m²/g,an average pore diameter of 6.0 to 15.0 nm and a pore volume of 0.2 to0.7 cm³/g, and a pore distribution of 20% of a pore volume of pores of 0to 5 nm, 70 to 85% of its pore volume of pores of 5 to 50 nm and lessthan 5% of said pore volume in pores with diameter greater than 50 nm,and a total acidity at 100° C., equivalent to 180 to 360 micromoles ofpyridine per gram of catalyst.
 6. The catalyst of claim 5, wherein saidcatalyst has 74-85% of the pores with a diameter in the range of 5-50nm.
 7. The catalyst of claim 1, wherein said catalyst has a porediameter of 6-12 nm.
 8. The catalyst of claim 1, wherein said catalystcomprised 9-12 wt % molybdenum and 2.8-4.4 wt % nickel.
 9. The catalystof claim 8, wherein said catalyst has surface area of 220-235 m²/g. 10.The catalyst of claim 9, wherein said catalyst has a pore volume of0.3-0.6 cm3/g, and average pore diameter of 6.6-9.2 nm, and a poredistribution of <5 nm in an amount of 13.6-23.3 vol %, 5-50 nm in anamount of 75.6-84.8 vol %, and >50 nm in an amount of 1.3-3.0 vol %. 11.The catalyst of claim 1, wherein said catalyst has a molybdenumconcentration of 10 wt % and a nickel concentration of 2.6 wt %.
 12. Thecatalyst of claim 1, wherein said catalyst comprised 74-85% of pores ina range of 5-50 nm.